Washing machine support assembly



Nov. 4, 1969 J, R. FOSLER ET AL 3,476,253

WASHING MACHINE SUPPORT ASSEMBLY 3 Sheets-Sheet l Filed Feb.

e n r of M m 5|@ o a /r mC/ www w 1 nb. T .m y JV Nov. 4, v1969 J. R.FOSLER ET AL 3,476,253

WASHING MACHINE SUPPORT ASSEMBLY Filed Feb. 4, 1965 v 3 Sheets-Shee 2 ll l l l l INVENTORS John R. FBsJez 825.91405 6. f/zazpe MZKKM THEIR A TTORNEY Nov. 4, 1969 J, R, FOSLER ET AL 3,476,253

WASHING MACHINE SUPPORT ASSEMBLY Filed F'e. 4, 1965 5 Sheets-Sheet 5 rDEFLEC TION w sHoRE DuRoMsrsR HARD/V555 commessa/0N OAD (Pouups) THEIRATTQRNEY United States Patent O 3,476,253 WASHING MACHINE SUPPORTASSEMBEYv John R. Fosler and Verlos G. Sharpe, Dayton, 9h10, as-

signors to General Motors Corporation, Detroit, Mich.,

a corporation of Delaware Filed Feb. 4, 1965, Ser. No. 430,266 Int. Cl.B01d 21/26; B041] 7/00; F16f 15/10 U.S. Cl. 210-365 1 Claim ABSTRACT FTHE DISCLOSURE A moving mass system including a spin tub rotatable on aspin shaft through a slip clutch drive mechanism below, and wherein thesystem is supported between the tub and the drive mechanism on aresilient cup shaped support of reduced spring rate and at its lower endon a freely relatively slidable snubber.

This invention relates to a domestic appliance and more particularly toan improved support arrangement for a roller drive mechanism foragitating and spinning of the type taught in the patent to Brucken3,087,321, issued Apr. 30, 1963.

In clothes washers having a. solid tub rotatable for centrifuging watertherefrom, it is desirable that the dynamic forces created duringspinning be restrained from vibrating or moving the clothes washercabinet. Prior systems directed to this problem are shown in the patentsto Sisson 2,859,877 issued Nov. 11, 1958, and to Clark et al. 2,539,530issued Jan. 30, 1951.

Accordingly, it is an object of this invention to provide in a clotheswasher an improved support arrangement for a moving mass systemcomprising a spin tub and roller drive mechanism.

Another object of this invention is the provision for a moving mass spintub system of an improved support arrangement comprising resilientsupport means connected to said moving mass system at a midpoint thereoffor vertically supporting approximately half of the weight thereof andfor absorbing some lateral dynamic forces eected lby the unbalancedrotation of the spin tub and comprising further a snubber at the bottomof said moving mass sys'tem for vertically supporting the remainingweight of said system and for absorbing the remaining lateral dynamicforces.

A further object of this invention is the provision of an improvedsnubber arrangement for an agitating and spinning drive mechanism whichhas improved assembly and reliability characteristics and which resistslateral excursions of said mechanism without denitely limiting themovement thereof.

A more general object of this invention is the provision of a supportarrangement for a moving mass spin tub system which is designed toretain the water in said spin tub until after said moving mass systempasses through the critical speed of the spin tub.

Another object is the provision of a suspension arrangement for a spintub wherein the lateral deflection at an upper portion thereof islimited and the lateral deflection at a lower portion thereof isunlimited.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein a preferred embodiment of the present invention isclearly shown.

In the drawings:

FIGURE 1 is a sectional View, partly in elevation, of a clothes washersuitable for use with the improved moving mass support system of thisinvention;

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FIGURE 2 is a fragmentary sectional view taken along line 2 2 in FIGURE1 showing the snubber portion of this invention;

FIGURE 3 is a fragmentary sectional view taken along line 3 3 in FIGURE2;

FIGURE 4 is a fragmentary sectional view, partly in elevation, of theresilient mechanism support portion of this invention showing itscondition when the spin tub is at standstill or in a balanced rotatingsituation;

FIGURE 5 is a fragmentary sectional view, partly in elevation, takenalong line 5-5 in FIGURE 4;

FIGURE 6 is a fragmentary sectional view similar to FIGURE 4 and showingthe mechanism support in a laterally stressed or distorted conditionresponsive to an unbalanced load in a rotating spin tub; and

FIGURE 7 is a graphic representation of the deflection curve for themechanism support of FIGURE 4.

For use with this invention and with reference to FIGURE l, a clotheswasher 20 is comprised of a control housing assembly 22 and a casing 24.The casing 24 is generally divided into a mechanism portion orcompartment 26 and a washing compartment or Water container chamber 28.A generally centrally located bulkhead 30 separates the mechanismcompartment 26 from the Water container chamber 28. Within the watercontainer chamber 28 is a spin tub 34 having a top opening 36 and aplurality of centrifuging outflow ports 38. The ports 38 are designed topermit the egress of water from the tub 34 when the tub is rotated athigh speed. For filling the tub 34 with water a conventional watersupply system may be provided wherein a hot and cold water solenoidoperated mixing valve is manifolded into a mixed water supply conduitterminating at a chute overlying the opening 36 of the tub. Within thetub 34, an agitator or pulsator 48 is adapted to reciprocate verticallyto circulate or agitate the water in the tub. Thus, clothing placedwithin the tub 34 is washed as the agitating action of the pulsator 48forces surging toroidal currents of washing fluid and detergent throughthe fabric. Conventional sequential operating timer means, showngenerally at 50` on the control housing 22, may be included selectivelyto admit water to the tub 34, to spin the tub and to verticallyreciprocate the agitator 0r pulsator 48.

:Roller drive mechanisms for selectively spinning a tub andreciprocating or oscillating an agitator are taught in theaforementioned Brucken patent, in Sisson Patents 3,060,712 issued Oct.30, 1962, and 3,165,911 issued lan. 19, 1965, and in copendingapplication Ser. No. 128,074 iiled July 3l, 1961, now Patent 3,174,596patented March 23, 1965, and assigned to the same assignee as thisinvention. This invention is directed to a suspension and snubbingsystem for use in combination with these roller drive mechanisms, andmore particularly with a slipping clutch drive mechanism of the typetaught in concurrently vtiled application Ser. No. 430,264, now Patent3,314,257 patented Apr. 18, 1967, one of which is shown generally at 51in FIGURE 1, said system serving to retain the water in the spin tubuntil after the tub is accelerated through its critical speed inaccordance with the teachings of this invention for reducing thecritical speed thereof.

In general the roller drive mechanism 51 is suspended from a stationaryshaft enclosing housing portion .54 which is connected to a resilientcup-shaped support member 56 and which encloses a spin shaft 55 and anagitate shaft 57. The support member 56, in turn, is a'lixed to anopening 58 in the bulkhead 30-a suitable sealing gasket Ibeing providedto effect a watertight connection therebetween. In order to dampenexcessive gyrating or swinging movement of the agitate and spinmechanisms lower end, a snubber device or assembly 70` is used at thelower end of a moving mass system which includes the spin tub 34 and theroller drive mechanism 51.

The agitating and spinning mechanism `51 includes a H P., split phase,single speed 1725 r.p.m., four-pole reversible motor 60l with a -builtin automatic reset type thermal overload protector. The motor, as wellas other components of the roller drive mechanism, are supported in asnubber support bracket 72 which is connected at the top thereof to thetubular support housing 54 and, at the bottom thereof, has a snubberplate 74 of bright zinc plated steel which is mounted thereto by fourscrews 76.

The surface 78 of the plate must be at within 0.010 inch, smooth andfree of burrs and imperfections or other protuberance which allowmaterial to protrude above the surface. Further, the plate should have achromate treatment and must be clean and free of dirt, oil and platingstreaks.

The snubber assembly 70 consists of a snubber 80 and a snubber spring 82held in a drawn cup portion 84 of a steel cabinet crossbrace 86. Thecrossbrace extends diagonally from one bottom corner of the clotheswasher cabinet 24 to another corner thereof, thereby strengthening thecabinet as well as retaining the snubber.

The snubber 80 is formed of sintered brass alloy and has a friction padportion `88 grooved for receiving wear particles, and a cylindricalsleeve Portion 90 having a downwardly faced opening formed by theterminal edge thereof. The pad portion mates closely with the flatsurface 78 on the snubber plate '74. The sleeve portion forms a cavitywhich receives the upper end of the coil spring 82. A spring retainer 92fastened to the crossbrace includes a drawn collar guide portion 94 forpositioning the lower end of the spring. Thus the spring helps to centerthe snubber pad.

Interposed between the snubber sleeve 90 and the drawn cup -84 is aresilient bushing or grommet 96 of synthetic rubber having an annulargroove for receiving a rolled edge of the cup. A lubricant impregnatedthin nylon liner 98 is assembled inside the rubber bushing to provide alubricated bearing and wear surface between the snubber and the bushing.As it is imperative that the mating snubber surfaces 7S, 88 be clean,the nylon insert also eliminates the presence of lubricant near thesnubber surfaces.

The rubber bushing 96 has a cylindrical sidewall 100 for yieldablyresisting the lateral thrust of the snubber 80 occasioned by therelative sliding movement between the snubber plate 74 and the snubberpad 88. A flange portion 102 on the bushing provides the lower stop forthe snubber pad 88.

In vthe suspension system of this invention the mechanism support 56 andthe snubber spring 82 are designed to each support about one-half of theweight of the mass system, i.e. the tub and its water and clothes loadplus the weight of the roller drive mechanism 51. Although the snubberpad 88 may bottom out on the bushing flange 102 when the tub is standingfull, these elements should be spaced apart as shown (FIGURE 2) duringspin. Further, the sliding friction surfaces 78 and 88 should be freelymovable relative to each other.

A relatively softer material has been chosen for the mechanism support56 than has been used heretofore in solid tub washers. For instance, andwith reference to FIGURE 7, curve A represents the hardness of thesupport 56 in washers exemplified by the aforementioned patents. Thecurves B and C represent the hardness range suitable for use with thesuspension system of this invention. These curves were developed byplacing the mechanism support 56 in a lixture, loading the top surface59 thereof and measuring the distance that the top surface 59 wasdeected downwardly. The hardness deiined by the range between curve Band curve C in conjunction 4with the improved snubber 70 holds thecritical speed of the spin tub to aronud 150 r.p.m.-a

speed more compatible for use with the slipping clutch roller drivemechanism disclosed in the concurrently filed application Ser. No.430,264, now Patent 3,314,257 granted Apr. 18, 1967. This means themoving mass system should be supported in a manner to provide a criticalspeed which is suiciently low that substantially all of the water willremain in the spin tub as added ballast until after the spin tub rotatesthrough its critical speed.

OUT OF BALANCE LOAD PROTECTION In the event that the load in the washertub is badly out of balance at the start of spin operation, the tub willtravel in an orbit as it rotates and the entire moving mass system willgyrate about a point generally at the flexible support 56. This orbitalmotion causes an increase in the amount of torque required to acceleratethe tub to full spin sped, which results in an increased load on theclutch plate of the slipping clutch roller drive mechanism taught inSer. No. 430,264, now Patent 3,314,257 patented Apr. 18, 1967.

As aforesaid, the merhanism support -56 is relatively softer than itscounterpart in earlier design roller drive mechanisms, and is softenedsufficiently to reduce the critical speed of the spin tub 34 toapproximately 150 r.p.m. as compared with speeds above 200 r.p.m. in theprior structures. The softening of the mechanism support lowers thespring rate so that with a given weight of the suspended mass, thefrequency of response is reduced, thereby resulting in a lower criticalspeed. The forces generated by the gyrations of the unbalanced spin tubare reflected at the snubber 70, where the freely movable cooperationbetween the snubber plate 74 and the snubber pad 8S act to snub theexcursions of the lower end of the moving mass system. With the clotheswasher of this invention, the resultant inertia load is always less thanthe force necessary to move the clothes washer cabinet 24.

During an unbalanced spin situation, the gyrations of the moving mass,including the spin tub, are limited at the support hat 56, by arestraining roller assembly 150. The roller assembly is comprised of asupport bracket 152 fastened to the support housing 54 of the agitatingand spinning mechanism 51. A retainer disc 154 fastened at 156 forms anannular channel or groove for cradling a nylon ring 158. If thegyrations of the moving mass become sutiicierrtly severe to effect thesituation shown in FIGURE 6, the nylon ring 158 will bump into thereinforced side of the support hat 56 and rotate in its annular channelas a means to stabilize and limit the gyrations of the tub. Thus theyieldable movements of the mechanism support 56 are limited while thesnubbing action is freely movable.

It should now be seen that an improved and simplified roller drivemechanism has been provided wherein the inertia forces on a moving masssystem are resisted by the combination of a relatively soft mechanismsupport and an improved freely movable snubber arrangement for themoving mass system. Moreover, the snubber arrangement is simplied anddesigned in a manner to prevent contaminants from reaching the slidingfriction surfaces thereof.

While the embodiment of the present invention as herein disclosed,constitutes a preferred form, it is to be understood that order formsmight be adopted.

What is claimed is as follows:

1. A washing machine including (a) casing means,

(b) a movable assembly comprising a vertical basket and slipping clutchdriving means located below said basket for rotating said basket,

(c) resilient supporting means connected to said casing means below saidbasket and connected to said driving means at its upper portion forsupporting approximately half the weight of said movable assembly,

(d) and snubber means for snubbing the movement of said movable assemblyrelative to said casing means,

(e) said snubber means comprising a snubber plate connected to saiddriving means at its lower portion, said snubber plate being free ofprotrusions therefrom, a snubber pad in contact with said snubber plateand freely relatively slidable thereto to permit extreme lateralmovement with respect thereto due to said snubber plate being free ofprotrusions and positioned substantially in a horizontal plane, andmeans for supporting said snubber pad and the remaining weight of saidmovable assembly,

(f) said last named means including a cylindrical sleeve integral withsaid snubber pad and forming a downwardly opening pocket, a coil springin said pocket extending between said casing means and said snubber padfor positioning said snubber pad and for vertically biasing said plateand pad together, and a resilient guide means connected to said casingmeans and surrounding said sleeve for resisting the lateral movement ofsaid snubber pad and for guiding the vertical sliding movement of saidsleeve,

(g) said guide means having a thin nylon facing in engagement with saidsleeve for minimizing the resistance to the sliding movement of saidsleeve,

(h) said guide means having a resilient stop portion between saidsnubber pad and said casing means for limiting the downward movement ofsaid movable assembly,

(i) said coil spring positioning said snubber pad a spaced distance fromsaid stop portion when said remaining weight of said movable assembly isbeing supported.

References Cited UNITED STATES PATENTS 2,381,894 8/1945 Ferris 68-23 X2,519,702 8/1950' Robinson 248-21 X 2,520,442 8/1950 Schwartz 248--3582,652,710 9/1953 De Reiner 210-365 X 2,667,269 1/1954 Reitz et al.210-365 2,680,585 6/1954 Crede 248-21 2,859,877 11/1958 SisSon 210-3652,896,937 7*/1959l Miller 267-1 20 sAMrH N. ZAHARNA, Primary Examiner W.S. ABRADBURY, Assistant Examiner U.S. Cl. X.R.

